[ 12 ° ] 
4* Thefe lingular exiflences afford ufeful in- 
ferences, and lhew that the irritability of the heart, 
is capable of being fuftained, by very low degrees of 
the nervous power, while that irritability is kept up by 
the foftering heat of the mother. This feeble life is 
foon extinguifhed, when the influences of the mother’s 
warmth and circulation ceafe (N°. j). Such infants 
die as fcon as born, or foon after.. 
.5. Such examples more confequentially than expe- 
riments demonftrate that the fpinal marrow is the 
principal origin of the intercoftal nerves (N°. 2.) ; and 
better than ligatures illuftrate their vaft importance, 
for, 
6. From the plump ftate of the body, and vigo- 
rous appearance of the heart, it is evident the circu- 
lation, and the developement of the feveral organs, 
had been carried on properly in the foetus ; and that 
the irritability of the heart derived a fufficiency of 
nervous influence from the intercoftal nerves, and its 
ganglions, and thefe again from the fpinal marrow, 
tor growth, and that ftate ofexiftence. 
In the eftay which was publifhed in the Philof. 
Tranf. for 1764, I endeavoured to prove, that as 
ganglions are ieated conftantly on the intercoftal 
nerves, and on others fent to mu teles whofe motions 
are involuntary, and are very rarely fecn on nerves 
lent to voluntary mufcles, and not at all on the fenfory 
nerves ; it feems that, by means of ganglions, the 
motions of the heart andinteftines and uvea are render- 
ed uniformly involuntary. I was then, and am ftill 
ienfible that various ftrong objections may be made 
to this dodtrine, in common with every other lyfteni 
whatever t but efpecially every fyftem which pretends 
to 
